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Space Science

Supermassive Black Holes Can Abort Star Formation 67

cremeglace writes "Astrophysicists have found that when a supermassive black hole quickly devours gas and dust, it can generate enough radiation to abort all the embryonic stars in the surrounding galaxy. It's not clear what this means for life's ability to take hold in such a bleak environment, but the research shows that the process might have determined the fates of many of the large galaxies in the universe."
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Supermassive Black Holes Can Abort Star Formation

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  • Effective (Score:1, Funny)

    by Anonymous Coward

    Is this even more effective than punching, stairs, or a coat hanger?

  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Friday April 16, 2010 @03:51PM (#31877068)
    Comment removed based on user account deletion
    • That's pretty far away, and radiation strength decays with an inverse square relationship to distance. I'd like to think we're safe.
      • Not to mention the speed of light introducing a mondo huge delay.

        • Until we can (if we can) exploit quantum mechanics to otherwise see this coming, it will be far too late to do anything about it.

        • Not to mention the mondo big red shift. Why are we so surprised? Matter and radiation densities rise as you head towards the galactic core. In this, very close case, it's enough to prevent star formation, ditto on the edge of the galaxy where the matter density isn't high enough for it to happen. There's bound to be a region in between where life-on-earth-suitable main sequence stars can ignite and evolve towards life friendly systems. It's an interesting piece of astrophysics in its own right, but any
    • Niven's story was entertaining, but from an astrophysics point of view it was sheer nonsense. Stars in binary systems routinely endure supernova explosions without exploding themselves. The idea of a chain reaction is not realistic.

    • by Khashishi ( 775369 ) on Friday April 16, 2010 @06:54PM (#31878998) Journal

      I think it's safe to say, if some galactic event is to obliterate the Earth, there's absolutely nothing we can do about it, so why worry?

      Although, it might be nice to know if it were happening soon, so we don't have to care about pollution, retirement, cancer, work, school ... and we can all have sex while high on heroin while skydiving with no parachute.

  • Polarizing (Score:4, Funny)

    by Itninja ( 937614 ) on Friday April 16, 2010 @03:52PM (#31877076) Homepage
    How long before Palin comes out against this? I am guessing it would go a little something like: 'Now the 'liberal elites' want us to think that God performs abortions?!'. Then she will follow up with various sentence fragments taken from a 'quote of the day' calendar.
  • Figures (Score:5, Funny)

    by Locke2005 ( 849178 ) on Friday April 16, 2010 @03:52PM (#31877086)
    As if we needed any more proof that black holes suck.
  • It's not clear what this means for life's ability to take hold in such a bleak environment

    Really?

  • I think "Supermassive Black Hole" in fact turned Muse into huge stars. Wait, isn't that what you're talking about?
  • Seems pretty clear to me. No stars, ..no supernova's, ..no condensed matter, ..no planets, ..no life as we know it. Short of some kind of bizarre plasma based lifeforms you could not expect to find ET. I think I will stay out of that part of the Universe just the same.
    • Stars which were already in those galaxies are still there, are they not? Life could've already developed there billions of years go. It just needs some singularity screen for the radiation.

      • by MBGMorden ( 803437 ) on Friday April 16, 2010 @07:30PM (#31879252)

        They are, but life typically forms around second or third gen stars. Before then, most of the matter in a galaxy is hyrdogen with a little helium thrown in. Only after a big round of massive stars + the associated supernovas do you start getting heavy elements in the proceeding star systems.

        The upside though is that according to the article, only 33% of the galaxies observed displayed this phenomenon. That's still a massive (the majority) number of galaxies that are just fine. Most importantly including our own. If we EVER achieve interstellar travel that'll be great, but interGALACTIC travel is almost certainly never going to happen (hell, even in Star Trek's far out there perfect future intergalactic travel is not feasible), so it doesn't really matter that much to us aside from scientific knowledge. Our galaxy is one of the good ones. Besides, the majority of galaxies appear to be dwarf galaxies, which would be unaffected by this.

  • Poor NASA. Now they're going to lose even more funding as Republicans and pro-life Democrats lobby to prevent NASA from using federal funds to investigate such phenomenon in the future.

    • by orkysoft ( 93727 )

      They can perform embryonic star cell research using federal funds now.

      Also, the singular is phenomenon, the plural is phenomena.</grammarnazi>

  • > It's not clear what this means for life's ability to take hold in such a bleak environment..."

    Please...who said anything about expecting life to 'take hold'...?

    James Bond: Do you expect me to talk?
    Auric Goldfinger: No, Mr. Bond. I expect you to die.
  • Pro light?
  • Good Slashdot post (Score:5, Interesting)

    by mbone ( 558574 ) on Friday April 16, 2010 @04:22PM (#31877446)

    For once, the Slashdot post is better than the original article.

    The cessation of star-making is not the same as the cessation of life. It might be good for life. It might be bad. All we really know right now is that this has not happened to the Milky Way galaxy, so we have a sample of one where it did not occur.

    The other thing missing in the original article is that galaxies are active things, and can and frequently do "eat" other galaxies - which brings new gas into the galaxy, and thus could restart star making (or make the black hole active again, or both).

    Here is an astrophysics prediction : this galaxies will have a high Mass to Light ratio, since gas and dust will be expelled, but not dark matter.

    • by painandgreed ( 692585 ) on Friday April 16, 2010 @04:55PM (#31877756)

      The cessation of star-making is not the same as the cessation of life. It might be good for life. It might be bad. All we really know right now is that this has not happened to the Milky Way galaxy, so we have a sample of one where it did not occur.

      The cessation of star-making is pretty much the same as the cessation of life. Without stars there will be no supernovas. Without supernovas, there will be no elements higher than the occasional helium atom. Unless we come up with a way to make a life form out of pure hydrogen, the lack of stars pretty much means the lack of life.

      • Re: (Score:3, Interesting)

        by icegreentea ( 974342 )
        It means that life that already started may not cease when supermassive black holes enter the super radiant (ha!) phase. The article mentions this phase lasts hundreds of millions of years. The estimated time of start of life on earth is like 4 billion years ago. So if the atmosphere of a life bearing planet can shield enough of the xrays, then life could well continue on a planet during the super radiant stage.

        It just means life (well, really stars) will end faster in those galaxies in the LONNGGG run.
        • Re: (Score:3, Interesting)

          by mbone ( 558574 )

          So if the atmosphere of a life bearing planet can shield enough of the xrays, then life could well continue on a planet during the super radiant stage.

          Exactly. Or, even if not, life could reform.

          Given the number of galaxies that the Milky Way has eaten (which would restock the missing gas), and the "missing" 500 million years or so of life in the very early history of our planet, I would not be too shocked if this had happened to the Milky Way a while ago, say 4.3 to 4.2 billion years ago. Of course, there

          • > If this happened now, some life on Earth, such as bacteria buried kilometers
            > down in the crust, would almost certainly survive it.

            What sort of intensity are we talking about here? A blast necessitating kilometers of shielding seems unlikely. That would, I think, vaporize the rock on the surface.

            • by mbone ( 558574 )

              What sort of intensity are we talking about here?

              I don't really know, and intensity is not the only thing - you need to know how it would affect the atmosphere, climate, biosphere, etc. and that depends on what state the the climate, atmosphere biosphere, etc., were in. I was just trying to provide an existence proof to show that something was likely to survive.

    • Sounds like the dark galaxy [arxiv.org] called VIRGOHI 21 [pparc.ac.uk] which might have ~1000x as much dark matter [iop.org] as visible matter (compare to ~10-20x for the Milky Way's ratio).
  • What sort of timescale are we looking at for such a galaxy to exhaust it's stars and become invisible to us? Could the void out there be full of "dark galaxies" that burned out fast and early and have no remaining active stars or are the supermassive galaxies being studies represent the first generation of such things to arise, presumably lingering on for many, many billions of years, dimming slowly as only the longest-lived stars remain?
    • by Bigjeff5 ( 1143585 ) on Friday April 16, 2010 @05:29PM (#31878206)

      What are these galaxies made of if not stars?

      Gas, lots and lots of gas.

      It's actually what stars are made of, along with the vast majority of planets. When stars super-nova, then they create dust, which can then become earth-like rocky planets. In baby galaxies and in galaxies with an active super-massive black hole, gas is being sucked in to the black hole so fast that it glows, It's like an ultra-massive star with a super-massive black hole core. The radiation from these black holes comes from the gas surrounding it falling in, not from the black hole itself. This radiation can potentially kick start other stars further out to form.

      Basically what the article is saying, is that a black hole can become so large, that if it activates again (new gas is introduced in some way, or it has simply had so much to consume that if finally hit the right size) that it can kill any young stars in the galaxy. That doesn't mean the older stars will be eliminated, because once a star reaches a certain size its own pressure maintains the reaction without external influence. It's the ones that are still collecting gas and are too small to maintain their own reaction that can be snuffed out.

      Furthermore, the gravity of a black hole, even a supermassive, has limits. Our solar system, for example, is well outside the range of the Milky Way's supermassive black hole - we are held in orbit by proximity to the mass of stars further from the center of the galaxy. So what you will end up with is not giant, invisible galaxies, but galaxies with a giant hole in the middle (like all galaxies with a non-active supermassive) and zero new star formation. It would take close to the heat death of the universe for them to become dark, and most galaxies will be nearly dark by then anyway.

    • by mbone ( 558574 ) on Friday April 16, 2010 @05:38PM (#31878316)

      What sort of timescale are we looking at for such a galaxy to exhaust it's stars and become invisible to us?

      Depends, but almost certainly >> the age of the Milky Way. After all, we have a bunch of globular clusters orbiting the galaxy, with no gas and all old stars, which are certainly still visible.

  • > a supermassive black hole quickly devours gas and dust, it can generate enough
    > radiation to abort all the embryonic stars in the surrounding galaxy. It's not
    > clear what this means for life's ability to take hold in such a bleak environment,

    For life that can exist in space without matter (gas, dust, stars, etc.) but with a large dose of radiation, it wouldn't mean much at all. Except that life is made of matter and thus it would get sucked in too.

    I would imagine that a supermassive black hole "c

  • We are spending way too much energy on stuff that is happening millions of light years away , how much is this costing us the tax payer to fund these discoveries that we can do without, seriously, have we come close to ending famine or curing cancer....i think those are the top 2 priorities, i understand we need to up to date to continue our moon missions and all, but what is happening so far away about these blackholes seems a bit to miss the point , no?

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